package javax.servlet;

import java.util.Enumeration;

/**
 * A servlet configuration object used by a servlet container to pass  information to a servlet during initialization.
 * servlet配置对象，servlet容器使用它在初始化期间向servlet传递信息。
 *
 */
public interface ServletConfig {

    /**
     * Returns the name of this servlet instance. The name may be provided via  server administration, assigned in the web application deployment
     * descriptor, or for an unregistered (and thus unnamed) servlet instance it  will be the servlet's class name.
     *
     * @return the name of the servlet instance
     */
    public String getServletName();

    /**
     * Returns a reference to the {@link ServletContext} in which the caller is executing.
     *
     * @return a {@link ServletContext} object, used by the caller to interact  with its servlet container
     * @see ServletContext
     */
    public ServletContext getServletContext();

    /**
     * Returns a <code>String</code> containing the value of the named  initialization parameter, or <code>null</code> if the parameter does not
     * exist.
     *
     * @param name a <code>String</code> specifying the name of the initialization parameter
     * @return a <code>String</code> containing the value of the initialization  parameter
     */
    public String getInitParameter(String name);

    /**
     * Returns the names of the servlet's initialization parameters as an
     * <code>Enumeration</code> of <code>String</code> objects, or an empty
     * <code>Enumeration</code> if the servlet has no initialization parameters.
     *
     * @return an <code>Enumeration</code> of <code>String</code> objects containing the names of the servlet's initialization parameters  ;
     *      包含servlet初始化参数名称的 String对象的枚举
     */
    public Enumeration<String> getInitParameterNames();
}
